1.Rebound depolarization of substantia gelatinosa neurons and its modulatory mechanisms in rat spinal dorsal horn.
Ling-Chao LI ; Da-Ying ZHANG ; Si-Cong PENG ; Jing WU ; Chang-Yu JIANG ; Tao LIU
Journal of Southern Medical University 2016;37(2):204-209
OBJECTIVETo investigate the rebound depolarization of substantia gelatinosa (SG) neurons in rat spinal dorsal horn and explore its modulatory mechanisms to provide better insights into rebound depolarization-related diseases.
METHODSParasagittal slices of the spinal cord were prepared from 3- to 5-week-old Sprague-Dawley rats. The electrophysiologic characteristics and responses to hyperpolarization stimulation were recorded using whole-cell patch-clamp technique. The effects of hyperpolarization-activated cyclic nucleotide gated cation (HCN) channel blockers and T-type calcium channel blockers on rebound depolarization of the neurons were studied.
RESULTSA total of 63 SG neurons were recorded. Among them, 23 neurons showed no rebound depolarization, 19 neurons showed rebound depolarization without spikes, and 21 neurons showed rebound depolarization with spikes. The action potential thresholds of the neurons without rebound depolarization were significantly higher than those of the neurons with rebound depolarization and spikes (-28.7∓1.6 mV vs -36.0∓2.0 mV, P<0.05). The two HCN channel blockers CsCl and ZD7288 significantly delayed the latency of rebound depolarization with spike from 45.9∓11.6 ms to 121.6∓51.3 ms (P<0.05) and from 36.2∓10.3 ms to 73.6∓13.6 ms (P<0.05), respectively. ZD7288 also significantly prolonged the latency of rebound depolarization without spike from 71.9∓35.1 ms to 267.0∓68.8 ms (P<0.05). The T-type calcium channel blockers NiCl2 and mibefradil strongly decreased the amplitude of rebound depolarization with spike from 19.9∓6.3 mV to 9.5∓4.5 mV (P<0.05) and from 26.1∓9.4 mV to 15.5∓5.0 mV (P<0.05), respectively. Mibefradil also significantly decreased the amplitude of rebound depolarization without spike from 14.3∓3.0 mV to 7.9∓2.0 mV (P<0.05).
CONCLUSIONNearly two-thirds of the SG neurons have rebound depolarizations modulated by HCN channel and T-type calcium channel.
Action Potentials ; Animals ; Calcium Channel Blockers ; pharmacology ; Calcium Channels, T-Type ; Cell Polarity ; Cesium ; pharmacology ; Chlorides ; pharmacology ; Cyclic Nucleotide-Gated Cation Channels ; antagonists & inhibitors ; Neurons ; cytology ; Patch-Clamp Techniques ; Pyrimidines ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Spinal Cord Dorsal Horn ; cytology ; Substantia Gelatinosa ; cytology
2.Role of oxytocin in neonatal rat hippocampal neurons after hypoxic-ische-mic injury
Chang-Ning XIE ; Jian WU ; Xin-Meng WANG ; Si-Cong PENG ; Jing WU ; Ling-Hui XIAO ; Tao LIU
Chinese Journal of Pathophysiology 2018;34(4):739-744,753
AIM: To investigate whether oxytocin has neuroprotective effects on hippocampal CA 1 pyramidal neurons from neonatal rats exposed to hypoxic-ischemic brain injury and the underlying mechanisms.METHODS:An in vitro model of hypoxic-ischemic injury was used by exposing the brain slices to oxygen-glucose deprivation(OGD)solution. Acute dissociated brain slices(6~8 slices per rat)from 8 Sprague-Dawely rats of 7~10 d old were used.The slices were randomly divided into 4 groups: control group, OGD 20 min group, OGD 40 min group and OGD +oxytocin group.The effect of oxytocin on neuronal death was evaluated by TO-PRO-3 staining.Fresh brain slices from other 20 neonatal rats were divided into OGD group,OGD+oxytocin group,OGD+dVOT(oxytocin receptor antagonist)+oxytocin group,and OGD+bicucuclline(GABAAreceptor antagonist)+oxytocin group.The onset of anoxic depolarization in the hippocampal neurons treated with different drugs was recorded by whole-cell patch-clamp techniques.RESULTS: The results of TO-PRO-3 staining showed that neuronal deaths in hippocampal CA 1 area were increased over the prolonged OGD time.Oxyto-cin significantly reduced the hypoxic-ischemic deaths.Oxytocin dramatically prolonged the onset time of anoxic depolariza-tion after the application of OGD solution.Both dVOT and bicuculline blocked this effect.CONCLUSION: Oxytocin plays a neuroprotective role in neonatal rat hippocampal CA 1 pyramidal neurons by enhancing the inhibitory synaptic trans-mission via oxytocin receptors.Therefore,oxytocin is useful as a candidate for neuroprotective treatment after neonatal hy -poxic-ischemic brain injury.
3.Influence of hypotension on the short-term prognosis of preterm infants with a gestational age of <32 weeks.
Chun-Hua LIU ; Si-Cong PENG ; Fang JIN ; Shi-Wen XIA
Chinese Journal of Contemporary Pediatrics 2022;24(11):1195-1201
OBJECTIVES:
To investigate the influence of early-stage hypotension defined as mean arterial pressure (MAP)
4.Effect of glucose metabolism disorders on the short-term prognosis in neonates with asphyxia: a multicenter study in Hubei Province, China.
Chun-Hua LIU ; Hui WANG ; Si-Cong PENG ; Wen-Xiang WANG ; Rong JIAO ; Sha PAN ; Tian-Jiao ZHU ; Xiao-Ying LUAN ; Xiao-Fang ZHU ; Su-Ying WU ; De-Guo WEI ; Bing-Feng FU ; Rui-Hong YAN ; Shu-Jie YANG ; Ya-Hui LUO ; Gui-Ping LI ; Min YANG ; De-Zhao JIA ; Chuang GAO ; Xiong-Fei XIAO ; Li XIONG ; Jie SUN ; Jia-Peng XIAO ; Bo-Wen LI ; Yan-Ni LI ; Lian-Hong ZHANG ; Tian-Guo LI ; Min CHENG ; Jian-Xin XIA ; Shi-Wen XIA
Chinese Journal of Contemporary Pediatrics 2021;23(12):1208-1213
OBJECTIVES:
To study the effect of glucose metabolism disorders on the short-term prognosis in neonates with asphyxia.
METHODS:
A retrospective analysis was performed on the medical data of the neonates with asphyxia who were admitted to 52 hospitals in Hubei Province of China from January to December, 2018 and had blood glucose data within 12 hours after birth. Their blood glucose data at 1, 2, 6, and 12 hours after birth (with an allowable time error of 0.5 hour) were recorded. According to the presence or absence of brain injury and/or death during hospitalization, the neonates were divided into a poor prognosis group with 693 neonates and a good prognosis group with 779 neonates. The two groups were compared in the incidence of glucose metabolism disorders within 12 hours after birth and short-term prognosis.
RESULTS:
Compared with the good prognosis group, the poor prognosis group had a significantly higher proportion of neonates from secondary hospitals (48.5% vs 42.6%,
CONCLUSIONS
Recurrent hyperglycemia in neonates with asphyxia may suggest poor short-term prognosis, and it is necessary to strengthen the early monitoring and management of the nervous system in such neonates.
Asphyxia
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Asphyxia Neonatorum/epidemiology*
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Humans
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Hyperglycemia
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Infant, Newborn
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Prognosis
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Retrospective Studies
5.Research progress on autophagic flux regulation in cataract
Cong-Yu WANG ; Peng-Fei LI ; Si-Wen WANG ; Si-Jie BAO ; Hai-Hong SHI ; Huai-Jin GUAN
International Eye Science 2023;23(9):1477-1481
Autophagic flux refers to a series of dynamic process of autophagic bilayer membrane formation, autophagosome formation, autophagolysosomes formation and degradation. The etiology of cataract is complex, including congenital abnormalities in lens development due to genetic mutations, oxidative damage due to aging, abnormalities in glucose metabolism due to diabetes, and proliferation of lens epithelial cells(LECs)stimulated by postoperative inflammatory factor, all of which are associated with the development of cataracts. A growing number of research in recent years have discovered that altering the status of LECs can contribute to the pathophysiological process of cataract by regulating autophagic flux. This review summarized the impacts of autophagic flux regulation on cataract.
6.Preparation and in vitro-in vivo evaluation of suvorexant orodispersible films
Peng ZHAO ; Cong-hui LI ; Si-yi SHUAI ; Bing YANG ; Hui ZHANG ; Nan LIU ; Ai-ping ZHENG ; Yong-jun WANG ; Zeng-ming WANG
Acta Pharmaceutica Sinica 2024;59(9):2659-2664
Orodispersible films (oral dispersible films), a novel form of oral solid dosage forms, are widely used for patients with dysphagia and those with uncontrollable autonomic behavior. In this study, suvorexant orodispersible film was prepared by hot melt extrusion technology, and the disintegration time, mechanical properties,
7.Rheology guided the preparation of suvorexant-copovidone solid dispersions via hot melt extrusion technology
Peng ZHAO ; Cong-hui LI ; Si-yi SHUAI ; Bing YANG ; Hui ZHANG ; Nan LIU ; Zeng-ming WANG ; Yong-jun WANG ; Ai-ping ZHENG
Acta Pharmaceutica Sinica 2024;59(8):2396-2403
The rheological properties of drug and carrier materials have a wide range of guiding significance for the formulation and process development of solid dispersions. In this study, the rheological properties of materials with different drug carrier ratios were systematically studied with suvorexant as the model drug and copovidone as the carrier material, which provided a sufficient basis for determining the formulation and process of solid dispersions. The optimal suvorexant-copovidone ratio obtained by oscillating temperature scanning was 1∶4. If the ratio is greater than 1∶ 4, the glass transformation temperature of the material will increase significantly, and the solubilization effect of the solid dispersion will show a downward trend. The results of oscillation temperature scanning and oscillation temperature sweep can show that when the extrusion temperature is greater than 150 ℃, the viscosity of the material is less than 10 000 Pa·s, and the melt can be extruded smoothly, and the best extrusion temperature of 160-180 ℃ can be obtained by combining the dissolution results. Finally, the dissolution of suvorexant tablets guided by rheological property studies in multiple media is similar to that of the commercially available tablets Belsomra. Therefore, rheological studies can screen and optimize the formulation and process of suvorexant solid dispersions at the mechanism level, which is of great significance to improve the success rate of R&D and shorten the R&D cycle of solid dispersions prepared by hot melt extrusion.
8.Herbalogical analysis of Aconiti Carmichaeli Radix.
Si-Han DONG ; Jie PENG ; Meng-Hua WU ; Zhi-Guo MA ; Cong-Long XU ; Hui CAO ; Ying ZHANG
China Journal of Chinese Materia Medica 2021;46(12):3156-3164
Tianxiong has been used as a Chinese medicinal in China for thousands of years, and the earliest record can be traced back to the Shennong's Classic of Materia Medica. It is effective in dispersing wind, dissipating cold, and replenishing fire to streng-then yang. To clarify the origin of Tianxiong, the present herbalogical study reviewed the ancient and modern literature from the origin, processing, and clinical efficacy. Before the Tang Dynasty, although the description of Tianxiong was quite superficial, an apparent difference between Tianxiong and Fuzi was recognized. In the Tang and Song Dynasties, Tianxiong and Fuzi were mistakenly recognized to be prepared from a same plant since their raw materials came from artificial cultivation. Medical literature in the Ming and Qing Dynasties mostly followed the previous records, with the origin of Tianxiong remaining controversial. There were three mainstream views about the origin of Tianxiong according the ancient medical books. First, Tianxiong was a kind of Aconiti Radix(Chuanwu) without attachment of Fuzi. Second, Tianxiong was the large Fuzi. Third, Tianxiong derived from Aconiti Kusnezoffii Radix(Caowu) about 10 cm in length. By contrast, Fuzi in a large size was simply regarded as Tianxiong in modern times. The processing methods were diversified in the ancient times, and the fire-processing was continuously applied. With the deepening of the research on the efficacy and detoxification mechanism, more methods were discovered, such as processing with ginger juice, child's urine and alcohol. As for modern times, the processing of Tianxiong has not been nearly passed down. The characteristic processing of Tianxiong only handed down in Sichuan province and Lingnan area, which can be discriminated by the last step. The efficacies of Tianxiong can be directly understood from its literal name, including dispersing wind, dissipating cold, and replenishing fire to assist yang. Nowadays, Tianxiong is mostly used to strengthen yang.
Aconitum
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Child
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China
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Drugs, Chinese Herbal
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Humans
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Materia Medica
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Medicine, Chinese Traditional
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Plant Extracts